Design philosophy in the Season 5 jungle

Now this isnt anything new as a majority of players have majorly criticized the new jungle. So this might come off as just another person complaining about the jungle but I just want to ask. Why? Why change the formula so drastically that the goal for "diversity" becomes more of a burden than it is a benefit. What I mean is that the diversity between a good jungle champion to a decent jungle champion became hell of a lot more apparent.

Here, we had Season 4 jungle. By which is almost perfect. They almost nailed it! They almost made a perfect jungle! You have great items that provide sustain and decent combat stats, and the jungle creeps werent that much a burden that there was a great diversity of junglers that Riot said they wanted to aim for! Now fast forward to the present in Season 5. They took a step forward with dragon and baron but took several steps back with almost everything else. Why is that? Why take drastic measure to change something from the majority liked to this mess. Im sorry but this is a literal mess.

I want to have a discussion as to why this happened the way it did. Did you design your new jungle around the actual player base or did you base it off of the top teir junglers?